This 2015 research paper, co-authored by Dr Hugo Dunlop, studied the effect of the route of administration on the mucosal and systemic immune responses to Lawsonia intracellularis vaccine in pigs.
In this on-farm study, 40 weaned piglets ages 3 weeks were vaccinated with Lawsonia intracellularis vaccine orally, IM or IP while a fourth group remained unvaccinated. All vaccinated animals showed increased serum levels of L. intracellularis IgG anti-bodies, but significantly elevated concentrations of specific IgG, IgA and cytokines were generated in ileal mucosal secretions from the orally and IP vaccinated pigs when examined at 17 days after vaccination.
